The present invention relates to a machine tool that has an improved cover for preventing swarf and cutting fluid from being scattered.
Japanese patent provisional publications Nos. P2000-190160 and P2000-288866 disclose machine tools having a cover, or splash cover, that prevents swarf and cutting fluid from being scattered around the machine tool. The splash cover includes four cover plates, i.e. a front cover plate extending upwardly from the front edge of a bed of the machine tool, right and left cover plates mounted on the right and left side edges of the bed, respectively, and a rear cover plate located between the rear edge of the bed and a rear device box in which various kinds of devices, such as a power source, a control device, a hydraulic pressure generator, and a coolant supplying device, are accommodated.
Generally, the splash cover has an opening on each of the front, right and left cover plates, which allows placing/removing of a workpiece to/from a work area of the machine tool and also allows maintenance of a tool interchanging device, for example. A sliding door or a flap door is provided to each opening so that a user can open and close the opening.
Some machine tools have a column that is mounted on an X-Y table so that the column can be moved on the bed in back and forth direction as well as in right and left direction, and a spindle is provided to the column movably in up and down direction with respect to the column. A cutting tool is attached to the end of the spindle. Such a machine tool works on a workpiece such that the column is moved toward a worktable place on the bed and then the spindle is moved downward.
The machine tool described above requires an open space above the rear portion of the bed to allow the column to move away from the worktable. When the column is placed in the vicinity of the worktable to carry out machining of the workpiece, a part of the X-Y table, which is located on the rear portion of the bed, or behind the column, is exposed to outside and allows the swarf of the workpiece to accumulate thereon. Therefore, the user has to regularly clean the X-Y table to remove the swarf accumulated on the X-Y table, in particular, on the part thereof behind the column. However, cleaning of the narrow space within the splash cover, especially behind the column, is not easy and often results in insufficient removal of the swarf.
Therefore, there is a need for a machine tool having a cover that effectively prevents the swarf from accumulating on the area behind the column.
The present invention is advantageous in that an apparatus that satisfies the need mentioned above is provided.
According to an aspect of the invention, there is provided a machine tool that includes a bed, a worktable mounted on the bed, a table mounted on the bed which is movable in back and forth direction relative to the worktable. The machine tool further includes a column, a spindle, a main cover and a back cover. The column is mounted on the table movably in a right and left direction. The column has a front side and a rear side. The front side of the column faces the worktable. The spindle is supported by the column movably in up and down direction. One end of the spindle is adapted to hold a tool for machining the workpiece. The main cover is mounted on the bed to prevent swarf of the workpiece from being scattered around the bed. The main cover is located at a front side and right and left sides of a space defined above the bed. The back cover is fixed to the table at the rear side of the column. The back cover is long in right and left direction of the bed.
In the machining tool arranged as above, the back cover effectively blocks the swarf of the workpiece and thereby prevents the swarf from being scattered toward and accumulating on the area behind the column.
Optionally, gaps are formed between side edges of the back cover and the main cover.
Optionally, the machine tool includes a coolant supplying device provided to the rear side of the bed, and a tube located between the coolant supplying device and the back cover to allow the coolant supplied from the coolant supplying device flowing therethrough.
Alternatively or additionally, the machine tool includes a power supply provided to the rear side of the bed, which provides power required for moving the column, and a cable located between the power supply and the back cover. The power is transmitted from the power supply through the cable.
Alternatively or additionally, the machine tool includes a control device provided to the rear side of the bed, which generates control signals for moving the column, a cable located between the control device and the back cover. The control signals are transmitted from the control device through the cable.
According to another aspect of the invention, a machine tool is provided that includes a column that can be moved back and forth. The column supports a spindle which is adapted to hold a tool for machining a workpiece at an end thereof. A worktable located in front of the column which is adapted to hold the workpiece. A back cover is located behind the column to prevent swarf of the workpiece from being scattered into a space behind the column. The back cover is arranged to move back and forth integrally with the column.
Optionally, the machine tool includes a table located behind the worktable. The table is movable toward and away from the worktable. The column is mounted on the table to be moved back and forth, and the back cover is fixed to the table to move integrally with the column.
The table may have a front side facing the worktable and a rear side, and the back cover may include a blocking plate supported by a plurality of supporting members fixed to the rear side of the table. The blocking plate may be arranged to block the swarf scattered toward the space behind the column.
In some cases, the blocking plate is made of a material having large tensile strength such as metal sheet. Alternatively or additionally, the blocking plate is made of a material having high chemical resistance. For example, the blocking plate a flexible board made of synthetic fibers.
Optionally, the machine tool includes a pair of cover plates located near right and left sides of the table in parallel to a moving direction of the table. The blocking plate is arranged between and substantially perpendicular to the pair of cover plates, and predetermined gaps are formed between side edges of the blocking plate and the pair of cover plates. The gaps are sufficiently wide to avoid being clogged with the swarf of the workpiece.
Optionally the machine tool includes a pair of table covers located on right and left side portions of the table extending beyond right and left sides of the column. The pair of table covers preventing swarf from accumulating on the right and left side portions of the table.
Further optionally, the column is movable along the table in right and left direction, and each of the table covers has a telescopic structure that expands and contracts so as to prevent the exposure of the table irrespective of the position of the column on the table in right and left direction.
Alternatively or additionally, each of the table covers being formed such that the swarf on the table cover slides down into a work area of the machine tool defined in front of the table.
Alternatively or additionally, the machine tool further includes an inclined cover fixed at a front side of the back cover, which extends substantially along the entire width of the back cover. The right and left side portions of the inclined cover are overlaid at least on a rear portion of the table covers so that swarf sliding down along the back cover is guided onto the plate covers by the inclined cover.
Further optionally, the machine tool further includes a roof shape cover placed on the inclined cover between the column and the back cover. The roof shape cover has right and left inclined surfaces connected to each other to form a ridge line of the roof shape cover. The right and left inclined surfaces are inclined such that the swarf slides down on the right and left inclined surfaces toward the right and left side portions of the inclined cover, respectively.
Further optionally, the machine tool further includes an inversely inclined cover fixed at a front end of the roof shape cover. The inversely inclined cover is inclined such that the rear end thereof is lower than the front end thereof.
Optionally, the machine tool further includes a device box that accommodates at least one device required for the operation of the machine tool. The back cover is located between the column and the device box.
Optionally, the machine tool is connected with a device box located behind the machine tool. The device box is connected with the machine tool with at least one of cable and tube. The at least one of cable and tube is located between the back cover and the device box.